Zoology , Endocrinology ( 404) By Dr Sadhana Shrivastava Spermatogenesis Reference books- Endocrinology of the male reproductive system and spermatogenesis- Liza O'Donnell, Peter Stanton, David Morritz de Kretser Handbook of Physiology Section 7 Endocrinology Volume V Male Reproductive System-R O Astwood, E B Greep
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Spermatogenesis · 2020-03-29 · Spermatogenesis Introduction : Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of
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Zoology , Endocrinology ( 404) By Dr Sadhana Shrivastava
Spermatogenesis
Reference books-
Endocrinology of the male reproductive system and spermatogenesis-
Liza O'Donnell, Peter Stanton, David Morritz de Kretser
Handbook of Physiology Section 7 Endocrinology Volume V Male
Reproductive System-R O Astwood, E B Greep
SpermatogenesisIntroduction :
Spermatogenesis is the process by which haploid
spermatozoa develop from germ cells in the
seminiferous tubules of the testis. This process starts
with the mitotic division of the stem cells located close
to the basement membrane of the tubules. Meiosis is
a step during spermatogenesis and oogenesis.
Spermatogenesis produces four
haploid sperm cells, while oogenesis produces one
mature ovum.
Two haploid spermatids (haploid cells) are generated by each
secondary spermatocyte, resulting in a total of four
spermatids. Spermiogenesis is the final stage
of spermatogenesis, and, during this phase, spermatids
mature into spermatozoa (sperm cells)
The seminiferous tubules, in which the sperm are produced,
constitute about 90 percent of the testicular… The immature
cells (called spermatogonia) are all derived from cells called
stem cells in the outer wall of the seminiferous tubules.
The process of producing mature sperm is called
spermatogenesis. Sperm are produced in the seminiferous
tubules of the testes and become mature in the epididymis.
The entire process takes about 9 to 10 weeks.
Spermatogenesis
Cross section through seminiferous tubule
12-6
Spermatogenesis
Stages:
Mitosis
Meiosis
Spermio-
genesis
Spermatids
Secondary
spermatocyte
Primary
spermatocyte
Spermatozoa
First meiotic
division
Second meiotic
division
One daughter cell remains
at the outer edge of the
seminiferous tubule to
maintain the germ cell line
One daughter cell moves
toward the lumen to
produce spermatozoa
Chromosomes:
46; 2n
(diploid number;
single strands)
46; 2n
(diploid number;
single strands)
46; 2n
(diploid number;
doubled strands)
23; n
(haploid number;
Single strands)
23; n
(haploid number;
double strands)
23; n
(haploid number;
single strands)
Spermatogonia
12-7
Steps of spermatogenesis
Figure 27.16
12-9
SPERMIOGENESIS (SPERMATID PHASE – haploid spermatid differentiates into sperm)